WO2019066557A1

WO2019066557A1 - Method and apparatus for decoding control information in wireless communication system

Info

Publication number: WO2019066557A1
Application number: PCT/KR2018/011530
Authority: WO
Inventors: 정의창; 박수영; 윤수하; 신승혁
Original assignee: 삼성전자 주식회사
Priority date: 2017-09-29
Filing date: 2018-09-28
Publication date: 2019-04-04
Also published as: KR20220146374A; KR20190038112A; US20220361163A1; US11425694B2; US11785601B2; US20240040570A1; US20200221439A1

Abstract

Disclosed is a 5G or pre-5G communication system for supporting a data transmission rate higher than that of a 4G communication system such as LTE. According to an embodiment of the present invention, a method for a terminal in a wireless communication system comprises the steps of: receiving system information and radio resource control (RRC) configuration information; checking decoding-related information including an aggregation level by using the system information and/or the RRC configuration information; and decoding control information on the basis of the aggregation level.

Description

Method and apparatus for decoding control information in a wireless communication system

The present invention relates to a wireless communication system, and more particularly, to a method and apparatus for decoding control information in a wireless communication system.

Efforts are underway to develop an improved 5G or pre-5G communication system to meet the growing demand for wireless data traffic after commercialization of the 4G communication system. For this reason, a 5G communication system or a pre-5G communication system is called a system after a 4G network (Beyond 4G network) communication system or after a LTE system (Post LTE). To achieve a high data rate, 5G communication systems are being considered for implementation in very high frequency (mmWave) bands (e.g., 60 gigahertz (60GHz) bands). In order to mitigate the path loss of the radio wave in the very high frequency band and to increase the propagation distance of the radio wave, in the 5G communication system, beamforming, massive MIMO, full-dimension MIMO (FD-MIMO ), Array antennas, analog beam-forming, and large scale antenna technologies are being discussed. In order to improve the network of the system, the 5G communication system has developed an advanced small cell, an advanced small cell, a cloud radio access network (cloud RAN), an ultra-dense network, (D2D), a wireless backhaul, a moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation Have been developed. In addition, in the 5G system, the Advanced Coding Modulation (ACM) scheme, Hybrid FSK and QAM Modulation (FQAM) and Sliding Window Superposition Coding (SWSC), the advanced connection technology, Filter Bank Multi Carrier (FBMC) (non-orthogonal multiple access), and SCMA (sparse code multiple access).

On the other hand, the Internet is evolving into an Internet of Things (IoT) network in which information is exchanged between distributed components such as objects in a human-centered connection network where humans generate and consume information. IoE (Internet of Everything) technology, which combines IoT technology with big data processing technology through connection with cloud servers, is also emerging. In order to implement IoT, technology elements such as sensing technology, wired / wireless communication, network infrastructure, service interface technology, and security technology are required. In recent years, sensor network for connecting objects, Machine to Machine , M2M), and MTC (Machine Type Communication). In the IoT environment, an intelligent IT (Internet Technology) service can be provided that collects and analyzes data generated from connected objects to create new value in human life. IoT is a field of smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliance, and advanced medical service through fusion of existing information technology . &Lt; / RTI >

Accordingly, various attempts have been made to apply the 5G communication system to the IoT network. For example, technologies such as a sensor network, a machine to machine (M2M), and a machine type communication (MTC) are implemented by techniques such as beamforming, MIMO, and array antennas It is. The application of the cloud RAN as the big data processing technology described above is an example of the convergence of 5G technology and IoT technology.

On the other hand, in the 5G system, the frame structure is changed, and thus a set of resources through which control information can be transmitted can be newly defined. Therefore, there is a need for a method for efficiently decoding control information.

The present invention has been proposed in order to solve the above-mentioned problems, and it is an object of the present invention to propose a method and apparatus for efficiently decoding control information.

According to another aspect of the present invention, there is provided a method of a terminal, including receiving system information and radio resource control (RRC) setting information, using at least one of the system information or the RRC setting information Determining decoding related information including an aggregation level, and decoding the control information based on the aggregation level.

According to another aspect of the present invention, there is provided a method of a base station for decoding a broadcast signal including an aggregation level using at least one of system information and radio resource control (RRC) Transmitting information and transmitting control information, wherein the control information is decoded based on the aggregation level.

According to another aspect of the present invention, there is provided a mobile station for receiving and transmitting system information and radio resource control (RRC) configuration information, And a controller for checking decoding related information including an aggregation level using at least one of the aggregation levels and decoding the control information based on the aggregation level.

According to another aspect of the present invention, there is provided a base station including a transceiver for transmitting and receiving signals,

Related information including an aggregation level using at least one of system information and radio resource control (RRC) setting information, and transmits control information, And is decoded based on the aggregation level.

According to the embodiment of the present invention, the overhead can be reduced by reducing the amount of information to be set for each terminal, and the control information can be efficiently decoded.

1 is a diagram showing a frame structure in a 5G communication system.

2 is a diagram illustrating a concept of search space and aggregation according to the present invention.

3 is a diagram illustrating a process of decoding control information according to an embodiment of the present invention.

4 is a diagram illustrating a specific process of decoding control information according to an embodiment of the present invention.

5 is a diagram illustrating monitoring period information according to an exemplary embodiment of the present invention.

6 is a diagram illustrating an example of determining AL information for each cell according to an embodiment of the present invention.

7A is a diagram illustrating a method for a base station to transmit decoding related information through UE-specific signaling according to an embodiment of the present invention.

7B is a diagram illustrating a method in which a UE receives decoding related information through UE-specific signaling according to an embodiment of the present invention.

8A is a diagram illustrating a method in which a base station transmits decoding related information through cell-specific signaling according to an embodiment of the present invention.

FIG. 8B is a diagram illustrating a method in which a UE receives decoding related information through cell-specific signaling according to an embodiment of the present invention. Referring to FIG.

9 is a diagram illustrating an operation of a UE when control information is transmitted through CORESET set in a separate resource according to an embodiment of the present invention.

10 is a diagram illustrating a structure of a BS and a UE according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The following terms are defined in consideration of the functions of the present invention, and these may be changed according to the intention of the user, the operator, or the like. Therefore, the definition should be based on the contents throughout this specification.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Currently, the concept of CORESET (s) is introduced in slot-based scheduling in 5G systems. CORESET means a control resource set (CORESET) for receiving control information. In the present invention, a control resource set and CORESET can be used in combination. Like the LTE, the 5G system (NR) considers blind decoding operation of the terminal for PDCCH decoding. In the current LTE, a frequency domain resource area in which a physical downlink control channel (PDCCH) may exist is fixed by a system bandwidth (BW) The resource area can find the number of symbols through the physical control format indicator channel (PCFICH). The corresponding PDCCH region may constitute a common search space and a UE-specific search space.

Meanwhile, the LTE system supports 1, 2, 4, and 8 aggregation levels. However, in the 5G communication system, it is necessary to consider aggregation levels such as 16 and 32 for additional blind decoding which is not supported in the LTE system, and optimal resource design and signaling are required for this. However, the embodiment of the present invention is not limited thereto, and the 5G communication system may support other aggregation levels (for example, 64). Considering this additional aggregation level, it may be necessary to link resources that take into account not only the aggregation level but also the composition of the common search space and the UE-specific search space. This means that it is a burden to unconditionally decode aggregation levels of 16 and 32, which are additionally considered for all UEs, and constraints that must be designed so as not to exceed the maximum number of blind decoding times (for example, 44) This is to complete the design to satisfy the requirements. In particular, a slot-level CORESET and a symbol-level CORESET within a single component carrier (CC) or one bandwidth part (BWP) When a plurality of PDCCHs (multiple PDCCHs) supporting beamforming are additionally considered, the number of blind decoding times increases and the number of blind decoding times increases. There is a need for solutions.

1 is a diagram showing a frame structure in a 5G communication system.

The design and various scenarios of CORESET and PDCCH candidates in a 5G communication system will be described with reference to FIG.

The CORESET structure can be configured as shown in FIG. As described above, CORESET means a set of resources through which control information can be transmitted. The CORESET includes a common control resource set (Common CORESET) to which common control information can be transmitted, and a common control resource set And a specific control resource set (UE-specific CORESET). In this case, the common CORESET and the UE-specific CORESET can be included in one CORESET, and they can be separately set as separate resources. In the present invention, the common CORESET and the UE-specific CORESET may be referred to as a first CORESET (first control resource set) and a second CORESET (second control resource set), respectively.

Specifically, one PDCCH candidates 115 may be included in one CORESET 110 as shown in FIG. 1 (a). For example, CORESET 110 may be a Common CORESET or a UE-specific CORESET, and may include a common search space or a UE-specific search space.

Alternatively, as shown in FIG. 1 (b), one CORESET 120 may include a plurality of

PDCCH candidates

121 and 123. For example, a common search space and a UE-specific search space may all be included in one CORESET 120, or a plurality of common search spaces or a plurality of UE-specific search spaces may be included in one CORESET 120.

Alternatively, as shown in FIG. 1C, a plurality of

CORESETs

130 and 140 may be separately set as separate resources. For example, one CORESET 130 is set to a common CORESET that includes the common search space 135, another CORESET 140 is set to a UE-specific CORESET that includes a UE-specific search space 145, .

Also, when the CORESET is set, the period may be set for a terminal monitoring the CORESET. Details will be described later. Specific characteristics of Common CORESET and UE-specific CORESET are as follows.

Common CORESET: refers to frequency and time resource region including common search space. Also, UE-specific search space may be included in some cases. The setting period of the Common CORESET or the Common CORESET monitoring period of the UE may be set through a radio resource control (RRC) or set to a default value.

UE-specific CORESET: refers to a frequency and time resource region including a UE-specific search space. The UE-specific CORESET can be set to multiple in a slot, and the period can be set different from the period of the Common CORESET. In addition to the slot-based CORESET, the CORESET of the symbol level may be set to one or more.

The UE may decode the control information through blind decoding in the search space of the Common CORESET or the search space of the UE-specific CORESET. At this time, the UE can perform blind decoding based on the aggregation level, and detailed contents of the blind decoding will be described below.

In the LTE system, four resource elements (REs) are composed of one resource element group (REG), nine REGs are composed of one control channel element (CCE) The control resource is transmitted in units of CCE.

On the other hand, in the 5G communication system, 12 REs can constitute one physical resource block (PRB) (1 PRB = 12 RE), and one PRB includes one REG (1 REG = 1 PRB) It can mean. And, one CCE can be composed of 6 REGs (1 CCE = 6 REG). Also, the 1/4 density is mapped to the DMRS, and the base station can actually use only 9 REs out of the 12 REs. The MCS used in this case can basically take QPSK into consideration.

A BS may transmit control information using a set of one or more CCEs, and a UE may retrieve control information from a set of one or more CCEs. At this time, the number of CCEs used for transmitting the control information or the unit of the CCE for searching the control information of the terminal may be referred to as an aggregation level.

Accordingly, the UE can arrange the REs constituting the control channel into CCEs and blind decode the control information according to the aggregation level.

Referring to FIG. 2, the UE may blind-decode the control

information using aggregation

1, 2, 4, and 8.

For example, if the aggregation level is 1 (210), the UE may attempt to decode the control information by incrementing the index by one from the CCE index 0.

Also, if the aggregation level is 2 (220), the UE can attempt to decode the control information by combining two CCEs into one unit. That is, the UE tries to decode the

CCE indexes

0 and 1, tries to decode the

CCE indexes

2 and 3.

At this time, the CCE to which the UE attempts to decode is referred to as a search space.

In this case, in the common search space, the aggregation level (AL) value may be set to the default type in order for the UE to decode the control information. Here, the meaning of default is that the terminal performs decoding assuming a certain number of times without any indication or configuration. For example, in the common search space, AL = 4, 8 can be set to the default type. Therefore, the UE can decode the control information by assuming a search space of AL = 4, 8. However, the embodiment of the present invention is not limited to this, and the AL value in the common search space may be separately set in the terminal by the base station. Details will be described later.

In the UE-specific search space, the aggregation level (AL) value may be supported as the default type or may not be supported in order for the UE to decode the control information. If the AL value is not supported by default, the AL value can be set by the base station.

In one embodiment, the aggregation level (AL) considered in the UE-specific search space may include 1, 2. This value is the value already supported in LTE. However, in the 5G system, since the structure of the CCE is different as described above, the size of the physical bits of the 5G system is different, which is not exactly the same resource. In another embodiment, the aggregation level (AL) considered in the UE-specific search space may include 16, 32. This can be designed to increase the decoding performance at the cell edge of the UE or to consider ultra-reliability in URLLC.

The DCI format includes resource related information, MCS information, CGB and HARQ related information (RV, NDI, HARQ process number, etc.), power control information, multi antenna related information, SRS related information, RNTI information, . An appropriate size (length) may be required to map the DCI information to the corresponding PDCCH resource. Size may or may not be mapped exactly to AL described above. If the mapping is not performed correctly, it may be repetition of all or part of the channel according to the channel condition.

Referring to FIG. 3, the terminal may receive decoding related information in step S310. The decoding related information may include AL information. At this time, the AL information can be set for each CORESET. Or AL information may be set on a cell-by-cell basis. Specific examples in which the AL information is determined on a cell-by-cell basis will be described later.

In addition, the decoding related information may include CORESET setting information. The CORESET configuration information may include at least one of common CORESET location information, Common CORESET period information, UE-specific CORESET location information, or UE-specific CORESET period information. However, the position or period information for the CORESET may be set in advance, and in this case, the UE may not receive the CORESET-related information. Alternatively, if location or period information for some CORESETs is preset, the terminal can receive the remaining CORESET-related information.

For example, the location information and the period information of the common CORESET may be predetermined, and the UE may receive location information and period information for the UE-specific CORESET.

Also, the AL information and the CORESET setting information included in the decoding related information may be transmitted through separate signaling. For example, the UE can receive Common CORESET configuration information and AL information about Common CORESET through a MIB or a synchronization signal, and can receive UE-specific CORESET configuration information and AL information through RRC information. Alternatively, if the common CRESET configuration information and the AL information are set to predetermined values, the UE receives the UE-specific CORESET configuration information through the RRC information and receives the AL information through the system information or the RRC information. However, the embodiment of the present invention is not limited to this, and AL information and CORESET setting information may be predetermined or signaled using at least one of the MIB or the synchronization signal, system information, and RRC information.

Thereafter, the terminal may decode the control information in step S320. The terminal may decode the control information according to the received decoding related information.

The above contents will be described in detail with reference to FIG.

The decoding-related information of FIG. 3 may be received through steps S410 through S450 of FIG.

Referring to FIG. 4, the terminal may receive a sync signal block in step S410. The synchronization signal block may be configured in the order of a primary synchronization signal (PSS), a physical broadcast channel (PBCH), a secondary synchronization signal (SSS), and a PBCH. Also, the synchronization signal block may be referred to as an SS / PBCH block.

In step S420, the terminal may acquire synchronization and master block information (MIB). At this time, the UE can confirm at least one of the location information, period information, and AL information of the common CORESET through the MIB or the synchronization signal. Alternatively, the above information may be predetermined by a default value.

The UE can receive the common control information through the common CORESET in step S430. The UE can decode the common control information by searching the search space within the common CORESET. At this time, the terminal can use the AL information or the default AL information confirmed through the MIB or the synchronization signal.

Then, the terminal can receive the system information in step S440. The UE can receive the system information based on the common control information received via the common CORESET. For example, the common control information received through the common CORESET may include RNTI information (SI-RNTI) for decoding the system information and information on the location of the resource to which the system information is transmitted, Information can be decoded.

In this case, the system information may include remaining minimum SI (RMSI) and other system information (other SI: OSI) excluding the MIB among the minimum system information (minimum SI).

The system information may include at least one of setting information for CORESET or AL information. However, according to the embodiment, the information may be transmitted through the RRC setting information, and the system information may not include the information.

Then, the MS may establish an RRC connection in step S450. At this time, the UE can confirm at least one of the configuration information or the AL information for the CORESET through the RRC configuration information received in the RRC connection establishment process. The RRC setting information may be transmitted including decoding related information not included in the system information.

The terminal can acquire the control information in step S460. The UE can decode the control information transmitted through the UE-specific search space or the UE-specific CORESET of the Common CORESET. At this time, the UE can decode the control information based on the obtained AL information, and as described above, the AL information can be received through the system information or through the received information when establishing the RRC connection .

Meanwhile, the BS of the present invention can determine decoding related information such as AL information and CORESET-related information for each cell, and transmit it to the terminal. For example, decoding related information may be transmitted to the terminal through system information or RRC information. Alternatively, a part of the decoding-related information may be predetermined by a default value and may be transmitted to the terminal through the MIB or the synchronization signal. Therefore, the UE can decode the control information using the obtained decoding related information for each cell. Details will be described later.

In the present invention, the CORESET period information may be referred to as monitoring period information or monitoring period information of CORESET.

As described above, the period information of the Common CORESET is set to the default value, or may be set in the UE through the MIB or the synchronization signal. Accordingly, the UE can acquire the control information by monitoring the CORESET according to the period information.

In addition, the period information of the UE-specific CORESET may be transmitted to the UE through RMSI / OSI information or higher layer signaling (RRC signaling). For example, if there is only one CORESET in the slot, the UE can confirm the set value through the upper layer signaling.

In this case, if there are additional CORESETs (eg UE-specific CORESET) or multiple CORESET scenarios considered in a multiple beam scenario, the monitoring periods may be the same for each CORESET, ). That is, the base station may set a cycle for each CORESET according to the design and configuration of the CORESET. CORESET may also be composed of one or a set of PDCCH candidates.

Referring to FIG. 5, the lengths of different periods may be set for each CORRSET. The period 510 of CORESET 1 may be set longer than the period 520 of CORESET 2 and the duration 515 of CORESET 1 may be set longer than the duration 525 of CORESET 2. In this way, different configuration information for each CORESET can be transmitted to the terminal.

In addition, different AL information for each CORESET can be set in the terminal as described above. At this time, the AL value may be set so as not to overlap with each CORESET. For example, if the value of AL in Common CORESET is set to 4, 8 by default, the AL value in the other CORESET can be set to a value that includes at least one of 1, 2, 16, In another example, if the AL value in the Common CORESET is set to 1, 2, 4, or 8 by default, the AL value in the other CORESET can be set to a value that includes at least one of 16 and 32. However, some values may be set to be duplicated.

Or the same AL information for one CORESET set may be set in the terminal.

Meanwhile, the 5G communication system considers a scenario in which a service is provided for each cell, and decoding related information can be determined for each cell according to a service or a cell coverage provided by the cell. The details will be described below.

Referring to Fig. 6 (a), A1 CORESET may include a common search space (CSS) and some or all UE-specific search space (USS). In this case, cell 1 has a common CORESET structure in A1 (610), and CSS and USS can be included in one CORESET. In this case, the combination of AL can be configured as shown in Table 1 below. The proposed combination of ALs does not limit the cases described in the table below, but can be extended to similar concepts. That is, the AL of Common CORESET and UE-specific CORESET can be mapped to A type and B type as shown in Table 1 below. However, the following table is only an example of the combination of AL, and the scope of the present invention is not limited thereto. That is, in the present invention, in addition to the combinations shown in Table 1, various combinations can be used using available AL values.

[Table 1]

For example, in Cell 1, A1 610 may be configured to support all aggregation levels in a common CORESET.

At this time, AL 16 or 32 may or may not be supported depending on the service (eMBB, UR, URLLC, mMTC, etc.) supported for each cell. In addition, depending on the cell radius, additional AL 16 or 32 can be supported if the NR cell link budget is poor.

Various additional embodiments for supporting AL 16 or 32 in supporting cell-specific configuration may exist as follows.

6 (b) and 6 (c) illustrate a case where common CORESET and UE-specific CORESET are set as separate resources.

For example, referring to FIG. 6B, in Cell 2, A2 620 may be configured to support some aggregation levels in a common CORESET.

At this time, the AL value in A2 (620) can be designed to support only 4, 8. It can be set to default or set in the terminal via MIB or sync signal, and can be applied in CSS considering general purpose DCI size. It may also be designed to decode the remaining

AL

1, 2, 16, or 32 in UE-specific CORESET resources (B1, 625). However, the embodiment of the present invention is not limited to this, and can be applied to cases where both A2 and B1 are UE-specific CORESET. That is, the AL value in A2 may be set in the UE via RMSI / OSI or RRC signaling to support only 4, 8 and may be designed to decode the remaining

AL

1, 2, 16 or 32 in another UE-specific CORESET resource have. In such a case, the AL value of the common CORESET may be determined to be default and may be overlapped with the AL value of the UE-specific CORESET.

If

AL

4 and 8 are performed in A2 (e.g., CSS) 620 as in combination 2, then B1 (e.g., USS) 625 may support

AL

1, 2, 16, or 32. Thus, the base station can design each search space to have a different AL value. Such a combination may exist in various ways, and Table 1 shows an example thereof.

In another embodiment, referring to FIG. 6C, in Cell 3 630, A3 may be configured to support some aggregation levels in a common CORESET.

At this time, it can be designed to support

AL

1, 2, 4, 8 in A2. It can be set to default or set in the terminal via MIB or sync signal, and can be applied in CSS considering general purpose DCI size. However, the embodiment of the present invention is not limited to this, and may be applied to the case where A2 is a UE-specific CORESET. In this case, the AL value supported by the A2 can be set in the UE through RMSI / OSI or RRC signaling.

If

AL

1, 2, 4, and 8 are performed in A3 (eg CSS) 630 as in combination 2, then AL 16 in B 2 (eg USS) 631 and 32 in B 3 (633) . Thus, each Search space can be designed to have a different AL value. Such a combination may exist in various ways, and Table 1 shows an example thereof.

If

AL

1, 2, 4, and 8 are performed in A3 (eg CSS), B2 (eg USS) can support AL 16 and 32. At this time, B3 can be designed so that some or all ALs are overlapped. In combination 4, AL 16 and 32 of B 3 are all overlapped with AL of B 2. However, they may overlap partially or additionally, overlapping AL values of A 1 (CSS). Thus, in a beamforming scenario, each TRP transmits a PDCCH, and the UE can receive and decode multiple CORESETs. At this time, the AL of B3 may include part or all of the AL of B2 (USS), and may additionally be set to include AL of CSS.

AL

1,2, 16, or 32 may or may not be supported depending on the service (eMBB, UR, URLLC, mMTC, etc.) supported by each cell. In addition, depending on the cell radius,

additional NR

1, 2, 16, or 32 can be supported if the NR cell link budget is bad.

In this case, B2 B3 is proposed to reduce the unnecessary decoding performed by the UE since the maximum decoding count within one slot is agreed to operate at less than 44 times of the LTE standard. In this case, CORESET is divided into cells We suggest a way to set up AL (UE specific is also possible).

In this manner, considering the service or coverage performance supported by the cell, an appropriate AL according to the CORESET is set for each cell, and a monitoring cycle is separately set for each CORESET, thereby reducing the number of decoding times of the UE.

On the other hand, a method of signaling the above-described information will be described below. In the present invention, information determined for each cell as described above may be individually transmitted to the UE through UE-specific signaling, or may be transmitted to the UE using broadcast information.

A broadcast or multicast signal (channel) may be used to transmit AL information using cell-specific configuration determined for each cell.

Specifically, as described above, the UE can perform the decoding of the common control information in the common CORESET in which the default AL (e.g., 4 or 8) is set or the AL value is set through the MIB or the synchronization signal. Then, the UE can receive RMSI or OSI information based on this. In this case, the RMSI or OSI information may include UE-specific CORESET or AL information about UE-specific search space of Common CORESET. Accordingly, the UE can perform decoding on the basis of the max AL information supported by the corresponding cell in the subsequent PDCCH decoding. Hereinafter, a specific example will be described.

1. If UE-specific search space is included in Common CORESET

In one embodiment, the UE for access / attach to cell 1 decodes the common control information using the value AL (

eg

1, 2, 4, 8) set to the default value before RRC connection in the corresponding CORESET (A1) Or to decode the common control information up to the maximum AL value (maximum AL) (eg 8). At this time, the base station can inform the UE of the maximum AL value for the common search space of the common CORESET (for example, via the MIB or the synchronization signal). Alternatively, the base station may inform the terminal of a set of specific AL values or AL values for the common search space of the common CORESET. Alternatively, the mapping information for the combination of the AL values may be predetermined, and the base station may transmit the index value for the combination of the AL values to the terminal. The method of transmitting the AL value can be applied to the first half of the present invention. Alternatively, a combination of the AL value or the AL value may be determined in the form of a table, and the BS may transmit the index value for the combination of the AL values in the table to the UE. Alternatively, the base station may inform the terminal of the maximum AL value as described above, or inform the terminal of the number of AL values to be used. When informing the number of AL values to be used, the terminal can determine an AL value to be used according to a predetermined rule. For example, the predetermined rule may be set to determine the AL value to use from the smallest value.

After RRC connected, the UE can decode the control information using the AL value in the same CORESET. At this time, the AL value (for example, 16 or 32) of the UE-search pace of the Common CORESET may be transmitted to the UE through system information or RRC signaling. The concrete transmission method is the same as described above.

Also, the UE can know the position of the CORESET A1 through the synchronization signal block (SSB) information, the information associated with the synchronization signal block (SSB), a predetermined position, and the like.

2. If UE-specific search space is not included in Common CORESET

In another embodiment, the UE for access / attach / camp on to cell 2 decodes the common control information using the AL value set to the default value before the RRC connection in the CORESET (A2) It is possible to perform decoding of the common control information. At this time, the method of receiving the AL value for CORESET (A2) is the same as described above.

The UE can decode the control information in the CORESET (B1) based on the RMSI information confirmed based on the common control information. Specifically, the base station can transmit the AL value through the RMSI information, the OSI information, or the RRC signaling, and the terminal can decode the control information using the AL value.

At this time, the terminal can know the position of each CORESET A2 through the synchronization signal block (SSB) information, the information associated therewith, or the terminal's spec. In addition, the UE may know the position of B2 through the information set in the RRC establishing step or the group common PDCCH reception (L1 signaling). That is, in the RRC establishing step, the base station may transmit information to the UE including the information for setting the AL together with the location of B1, and only the location of the UE-specific configuration of AL for CORESET B1 is set in the RRC establishing step, And the mapping or the mapping relation may be included in the RMSI information and transmitted to the terminal. In addition, a group common PDCCH may be considered additionally.

3. If the UE-specific search space is partially included in the Common CORESET

In another embodiment, the UE for access / attach / camp on to cell 3 decodes the common control information using the default AL value before the RRC connection in the corresponding CORESET (A3) Lt; / RTI > At this time, the method of receiving the AL value for CORESET (A2) is the same as described above.

The UE can decode the control information in the CORESET (B2) based on the confirmed RMSI information based on the common control information. In addition, B3 supports redundant AL, so that in a beamforming scenario, each TRP transmits control information on the PDCCH, and the UE can decode control information received via multiple CORESET. At this time, the AL value of B3 may include some or all of the AL value of B2, and may additionally be set to include the AL value of CSS. In this way, it is possible to maintain and support a certain service in a certain slot by decoding CORESET of a symbol level only.

At this time, the terminal can know the position of each CORESET A3 through the SSB information, the information associated therewith, or the spec of the terminal. Also, the UE may know the location of B2 / B3 through the information set in the RRC establishing step or through the group common PDCCH reception. (L1 signaling).

That is, in the RRC establishment step, the base station may transmit information including the information of setting the AL together with the positions of B2 and B3 to the mobile station, and only the positions of B2 and B3 (UE-specific configuration of AL for CORESET) And the support or mapping relationship between AL and CORESET can be included in the RMSI information and transmitted to the UE. In addition, a group common PDCCH may be considered additionally.

Meanwhile, as described above, the monitoring period can be set for each CORESET. The method of setting the monitoring period can be classified according to the structure of Common CORESET and UE-specific CORESET. For example, if Common CORESET and UE-specific CORESET are included in one CORESET, the monitoring period can be set to the same period (p1). If Common CORESET and UE-specific CORESET are set on separate resources, the monitoring period can be set to different periods p1 and p2, respectively. At this time, the values of p1 and p2 can be set differently. The specific setting method is described below.

The monitoring period can be set for each candidate (s) of each PDCCH. In one embodiment, the monitoring period can be set separately for each value of AL. Table 2 below shows a case in which the period can be set and the case where the PD of the PDCCH applied in the actual cell is distinguished by the AL. However, the following Table 2 is only an example of the monitoring period classified by AL, and the scope of the present invention is not limited thereto. That is, in the present invention, in addition to the combination of the AL value and the monitoring period shown in Table 2, the AL period and the monitoring period may be combined to set the monitoring period for each AL value. In addition, the base station of the present invention may set the monitoring period to the terminal using a method other than the method described in Table 2. [

[Table 2]

According to Table 2, if the aggregation level is set to 8, the monitoring period may be set to any one of 1, 2, and 3. The relation between the value of the aggregation level and the monitoring period may be mapped in advance, and the UE can check the monitoring period using the aggregation level value. However, when a plurality of monitoring periods are mapped as shown in Table 2, information on which value is to be used may be additionally transmitted to the UE.

The monitoring period can be determined through SSB information, information associated with it, and the specifics of the terminal. It is also possible to know the information set in the RRC establishment step or the group common PDCCH reception. (L1 signaling). For other embodiments, the monitoring period may be included in the RMSI / OSI information. The setting method for each candidate AL of the PDCCH can be the same as the common CORESET method.

On the other hand, the method of setting the monitoring period is not limited to the above. That is, the base station can set the monitoring period separately from the AL value for each CORESET. For example, a plurality of monitoring periods that can be set may be predetermined, and the base station may select any one of the CORESETs and transmit the same. For example, a configurable monitoring period may be predetermined in units of slots or units of time, and the base station may set one of the monitoring periods to the terminal. Alternatively, the monitoring period to be set is not fixed, and the length of the monitoring period for which the base station is to be set can be informed to the terminal by using bit information or the like on a slot basis or a time basis. However, the above description is merely an example of setting the monitoring period, and the monitoring period can be set by various methods.

The configuration overhead can be reduced by setting the aggregation level of the CORESET to be set for each UE connected to the cell through the above method for each cell in consideration of the service or coverage performance supported by the cell. In addition, it is possible to reduce the number of PDCCH decoding of the UE by arranging an appropriate AL according to the resource allocation of the CORESET. In addition, the number of decoding can be reduced by dividing the monitoring period by CORESET or AL.

Referring to FIG. 7A, the BS transmits an SS / PBCH block in step S710, and transmits a first CORESET in step S711. In this case, the first CORESET may mean common CORESET, and the process of transmitting the first CORESET may be a process of transmitting common control information through the first CORESET. The base station may transmit common control information based on a predetermined default AL value, determine an AL for the first CORESET, and transmit common control information using the determined AL. The common control information may include information necessary for the terminal to receive the system information, and the details thereof are the same as those described above.

The base station can transmit the system information in step S712. The system information may include RMSI information and OSI information, and the details are the same as those described above.

In step S713, the BS may transmit the RRC connection setup information to the MS. At this time, the RRC connection setting related information may include the second CORESET setting information and the AL information.

The second CORESET setting information may include position and period information of the second CORESET, and the AL information may include information determined for each cell. However, the embodiment of the present invention is not limited thereto, and the AL information may include information set for each terminal. The first CORESET and the second CORESET are not necessarily limited to the time frequency resources.

The details of the AL information determined for each cell or each terminal are the same as those described above, and will not be described below.

Then, the BS can transmit control information using the AL information in the second CORESET (or UE-specific search space of the first CORESET).

Referring to FIG. 7B, the terminal receives the SS / PBCH block in step S720 and obtains the registration and MIB information in step S721. Then, the terminal can receive the first CORESET in step S722. The details are the same as those of steps S410 to S430 of FIG. In this case, the first CORESET may mean common CORESET, and the process of receiving the first CORESET may be a process of receiving common control information through the first CORESET. The UE can receive common control information based on a predetermined default AL value or receive the AL for the first CORESET through the SS / PBCH block and receive common control information using the received AC / SS. The common control information may include information necessary for the terminal to receive the system information, and the details thereof are the same as those described above.

Then, the terminal can receive system information in step S723. The system information may include RMSI information and OSI information, and the details of the system information are the same as those of step S440 of FIG.

Then, the terminal can establish an RRC connection in step S724. At this time, the terminal can receive the second CORESET configuration information. Also, the terminal can receive the AL information. The AL information may be information for decoding the control information transmitted in the second CORESET. However, the present invention is not limited to this, and may include information used to decode control information transmitted through a common search space of a first CORESET.

The second CORESET setting information may include position and period information of the second CORESET, and the AL information may include information determined for each cell. However, the embodiment of the present invention is not limited thereto, and the AL information may include information set for each terminal.

Therefore, the UE can confirm the AL information through the RRC setting information.

The terminal can receive the control information in step S725. Specifically, the UE can decode the control information in the second CORESET (or the UE-specific search space of the first CORESET) based on the AL information and the CORESET setting information.

7A and FIG. 7B may be modified in different manners. In addition, the present invention can be set to include only some of the elements of the drawings without departing from the essence of the present invention.

Referring to FIG. 8A, the BS transmits the SS / PBCH block in step S810 and may transmit the first CORESET in step S811. The details are the same as those described above.

The base station can transmit the system information in step S812. At this time, AL information may be included in the system information. That is, the BS broadcasts the system information including the AL information for each cell and transmits the AL information to the terminal. The AL information may be information for decoding the control information transmitted in the second CORESET. However, the present invention is not limited to this, and may include information used to decode control information transmitted through a common search space of a first CORESET.

At this time, the AL information may be included in RMSI information or OSI information.

In addition, the AL information may include information determined for each cell. However, the embodiment of the present invention is not limited thereto, and the AL information may include information set for each terminal. The details of the AL information determined for each cell or each terminal are the same as those described above, and will not be described below.

In step S813, the BS may transmit the RRC connection setup information to the MS. At this time, the RRC connection setting related information may include the second CORESET setting information.

The second CORESET setting information may include the position and period information of the second CORESET.

However, the embodiment of the present invention is not limited thereto, and the second CORESET configuration information may be transmitted through the system information.

The base station can transmit control information using the AL information in the second CORESET (or UE-specific search space of the first CORESET).

Referring to FIG. 8B, the SS receives the SS / PBCH block in step S820 and obtains the registration and MIB information in step S821. Then, the terminal can receive the first CORESET in step S822. The details are the same as those described above.

Then, the terminal can receive system information in step S823. The system information may include AL information, and the details are the same as those described above.

Therefore, the terminal can confirm the AL information based on the system information.

Then, the terminal can establish an RRC connection in step S824. At this time, the terminal can receive the second CORESET configuration information. The second CORESET configuration information may include the position and period information of the second CORESET.

Accordingly, the terminal can receive the control information in step S825. The UE may decode the control information in the second CORESET (or the UE-specific search space of the first CORESET) based on the AL information and the CORESET setting information.

8A and FIG. 8B may be modified in accordance with the order of execution of the processes and the inclusion of the detailed operation. In addition, the present invention can be set to include only some of the elements of the drawings without departing from the essence of the present invention. For example, the terminal may receive the system information and confirm the AL information after establishing the RRC connection.

9, the UE receives the SS / PBCH block in step S910, and obtains the registration and MIB information in step S920. Then, the terminal can receive the first CORESET in step S930. The details are the same as those described above.

Then, the terminal can receive the system information in step S940. Then, the terminal can receive system information in step S723. The system information may include RMSI information and OSI information, and the details are the same as those described above.

Then, the terminal can establish an RRC connection in step S950. At this time, the terminal can receive the second CORESET configuration information. The second CORESET setting information may include the position and period information of the second CORESET, and the details are the same as those described above. Also, as described above, the second CORESET information may be transmitted to the UE through the system information.

Then, the terminal can confirm the AL information in step S960. The AL information may be information for decoding the control information transmitted in the second CORESET. However, the present invention is not limited to this, and may include information used to decode control information transmitted through a common search space of a first CORESET.

The base station may broadcast the AL information using the system information or may transmit the AL information to the terminal using the RRC configuration information in the RRC connection establishment step. Accordingly, the UE can confirm the received AL information through the system information or the RRC setting information. At this time, the AL information can be determined for each cell or for each terminal, and the details are the same as those described above.

Then, the terminal can receive the second CORESET in step S970. The process of receiving the second CORESET may be a process of receiving the control information transmitted through the second CORESET. The UE can decode the control information in the second CORESET using the second CORESET configuration information and the AL information identified above.

On the other hand, it is possible to modify the procedure and the detailed operation of FIG. 7A and FIG. In addition, the present invention can be set to include only some of the elements of the drawings without departing from the essence of the present invention. For example, the step of confirming the AL information may be omitted, and if the AL information is received through the system information, the terminal may check the AL information before establishing the RRC connection.

1 through 9 can be implemented by combining some components within the scope of not hurting the essence of the present invention.

Referring to FIG. 10, the base station may include a transmission / reception unit 1010 and a control unit 1020. In the present invention, the control unit may be defined as a circuit or an application specific integrated circuit or at least one processor. The processor may also be controlled by a program that includes instructions to perform the methods described in the embodiments of the present disclosure. The program may also be stored in a storage medium, which may include volatile or non-volatile memory. The memory may be a medium capable of storing data, and there is no restriction on the form when the instruction can be stored.

The transmitting and receiving unit 1010 may include a transmitting module and a receiving module, and may transmit and receive signals. For example, the transmission / reception unit 1010 can transmit a synchronization signal block and system information to a terminal and can transmit control information.

The controller 1020 can control the overall operation of the base station proposed by the present invention. The controller 1020 may control the signal flow between each block to perform the operation according to the flowcharts described above. For example, the control unit 1020 may control to transmit decoding related information for decoding the control information to the terminal.

Further, the base station of the present invention may include a storage unit. The storage unit may store at least one of the information transmitted / received through the transmission / reception unit 1010 and the information generated through the control unit 1020.

10, the terminal may include a transmission / reception unit 1030 and a control unit 1040. [ In the present invention, the control unit may be defined as a circuit or an application specific integrated circuit or at least one processor. The processor may also be controlled by a program that includes instructions to perform the methods described in the embodiments of the present disclosure. The program may also be stored in a storage medium, which may include volatile or non-volatile memory. The memory may be a medium capable of storing data, and there is no restriction on the form when the instruction can be stored.

The transmission / reception unit 1030 may include a transmission module and a reception module, and may transmit and receive signals. For example, the transceiver unit 1030 can receive a synchronization signal block and system information from a terminal and can receive control information.

The controller 1040 can control the overall operation of the terminal proposed by the present invention. The controller 1040 may control the signal flow between each block to perform the operation according to the flowcharts described above. For example, the control unit 1040 may receive decoding related information for decoding the control information, and may control to decode the control information.

In addition, the terminal of the present invention may include a storage unit. The storage unit may store at least one of information transmitted / received through the transmission / reception unit 1030 and information generated through the control unit 1040.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. Accordingly, the scope of the present invention should be construed as being included in the scope of the present invention, all changes or modifications derived from the technical idea of the present invention.

Claims

A method of a terminal in a wireless communication system,

Receiving system information and radio resource control (RRC) setting information;

Confirming decoding related information including an aggregation level using at least one of the system information and the RRC setting information; And

And decoding the control information based on the aggregation level.
The method according to claim 1,

Wherein the aggregation level is determined for each cell so that the aggregation level is not overlapped with the aggregation level determined for the first control resource set included in the same cell as the second control resource set to which the control information is transmitted,

Wherein the first control resource set is transmitted with common control information.
3. The method of claim 2,

Wherein the aggregation level is determined based on a type of a service provided by the cell or a coverage of the cell.
3. The method of claim 2,

Wherein the decoding related information includes setting information for the second control resource set,

Wherein the decoding step comprises:

And decoding control information based on the aggregation level in the second set of control resources,

Wherein the setting information for the second set of control resources includes at least one of position information or period information of the second set of control resources,

Wherein the setting information for the second control resource set is received through the RRC setting information, and the aggregate level is received through the RRC setting information or the system information.
A method of a base station in a wireless communication system,

Transmitting decoding related information including an aggregation level using at least one of system information and radio resource control (RRC) setting information; And

And transmitting control information,

And the control information is decoded based on the aggregation level.
6. The method of claim 5,

Wherein the aggregation level is determined for each cell so that the aggregation level is not overlapped with the aggregation level determined for the first control resource set included in the same cell as the second control resource set to which the control information is transmitted,

Wherein the first control resource set is transmitted with common control information.
The method according to claim 6,

Wherein the aggregation level is determined based on a type of a service provided by the cell or a coverage of the cell.
8. The method of claim 7,

Wherein the decoding related information includes setting information for the second control resource set

Wherein the control information is decoded based on the aggregation level in the second set of control resources,

Wherein the setting information for the second set of control resources includes at least one of position information or period information of the second set of control resources,

Wherein,

Transmitting configuration information for the second control resource set through the RRC configuration information, and transmitting the aggregation level through the RRC configuration information or the system information.
A terminal in a wireless communication system,

A transmitting and receiving unit for transmitting and receiving signals; And

System information and radio resource control (RRC) setting information,

Related information including an aggregation level using at least one of the system information and the RRC setting information,

And a control unit for decoding the control information based on the aggregation level.
12. The method of claim 11,

Wherein the aggregation level is determined for each cell so that the aggregation level is not overlapped with the aggregation level determined for the first control resource set included in the same cell as the second control resource set to which the control information is transmitted,

Wherein the first control resource set is transmitted with common control information.
13. The method of claim 12,

Wherein the aggregation level is determined based on a type of a service provided by the cell or a coverage of the cell.
13. The method of claim 12,

Wherein the decoding related information includes setting information for the second control resource set

Wherein,

Decode the control information based on the aggregation level in the second set of control resources,

Wherein the setting information for the second set of control resources includes at least one of position information or period information of the second set of control resources,

Wherein the setting information for the second control resource set is received through the RRC setting information, and the aggregate level is received through the RRC setting information or the system information.
A base station in a wireless communication system,

A transmitting and receiving unit for transmitting and receiving signals; And

Transmitting decoding related information including an aggregation level using at least one of system information and radio resource control (RRC) setting information,

And a control unit for transmitting control information,

And the control information is decoded based on the aggregation level.
17. The method of claim 16,

Wherein the aggregation level is determined for each cell so that the aggregation level is not overlapped with the aggregation level determined for the first control resource set included in the same cell as the second control resource set to which the control information is transmitted,

Wherein the first control resource set is transmitted with common control information.
18. The method of claim 17,

The aggregation level is determined based on the type of the service provided by the cell or the coverage of the cell,

Wherein the decoding related information includes setting information for the second control resource set,

Wherein the control information is decoded based on the aggregation level in the second set of control resources,

Wherein the setting information for the second set of control resources includes at least one of position information or period information of the second set of control resources,

Wherein,

Wherein the base station transmits configuration information for the second control resource set through the RRC configuration information and transmits the aggregation level through the RRC configuration information or the system information.